Both Johnson & Johnson and Danish partner Bavarian Nordic have induced a lasting immune response for a full year in 100% of vaccinated healthy volunteers, researchers reported. The world should be much better prepared for the next Ebola epidemic, with other promising results showing the potential of a long-lived lethal virus vaccine.
"The persistence of immunity induced by the vaccine at one year after vaccination is truly impressive," said researcher Matthew Snape of Oxford University. "The fact that all participants retained antibodies specific to Ebola at the end of the study raises the hope that this vaccine could induce responses that last for several years."
The vaccine requires one dose to prime the immune system and a second shot to boost the body's response. This is different from another Merck Ebola vaccine, which was the first to prove effective in preventing human infections during a large trial in Guinea the year.
Scientists have been racing to develop vaccines for Ebola after more than 11,300 people died in the West African epidemic 2013-2016. Recent advances mean that experts are now confident that the world will not be defenseless when the next episode strikes. While the rVSV-EBOV vaccine from Merck could be deployed to provide a "ring vaccination" of people in recent contact with new cases of Ebola, a more sustainable option could be a better bet for healthy support workers Entering to fight the crisis.
The prime-boost vaccine developed by J & J and Bavarian Nordic is currently being tested in major global trials that include over 1,000 subjects in Africa. The results of these studies are still awaited, but the vaccine has already been submitted to the World Health Organization for evaluation and the list of emergency uses, which could allow its accelerated deployment in the event of an Ebola crisis.
J & J said it has a stock of 1.8 million dosing regimens waiting in the gel, with the ability to produce several million more if needed. "We are so much more advanced now than two or three years ago," said Paul Stoffels, J&J's chief scientific officer. "We are ready to intervene if tomorrow there was a new emergency." Keith Chappell from the University of Queensland said the data to date was encouraging, especially since the J&J vaccine was non-replicating and therefore potentially safer than the Merck shot.
The findings, based on a Phase I clinical trial involving 75 healthy subjects, were published in the Journal of the American Medical Association.
